1. Field of the Invention
The present invention relates to a connection structure of a metallic tank for use in a heat exchanger of automobiles, etc.
2. Description of the Related Arts
The conventional heat exchanger metallic tank is provided with an elongated box-shaped tank body having an open end, and a tube plate adapted to block the open side. The tank body is manufactured through a plurality of deep drawing steps by means of press machines.
In case of manufacturing the tank body through the plurality of press drawing steps, a plurality of dedicated molds are needed increasing the cost for the manufacture of the molds, which results in a higher price of the heat exchanger as a whole.
When the tube plate is fitted and brazed to the tank body opening, the fitting portions at corners, esp., of the tank body and the tube plate may not necessarily be in registration with each other. This is attributable to a possible spring back or the like in the press forming. As a result, a leak may occur from the fitting portion at the corners after brazing.
It is therefore the object of the present invention to overcome the above deficiencies.
In order to attain the above object, according to a first aspect of the present invention there is provided a heat exchanger tank structure comprising:
a tank body formed from a bent metal plate in the shape of an elongated groove, the tank body having a bottom and two parallel sidewalls;
a tube plate having an open side which confronts the bottom of the tank body, the open side adapted to securely be fitted to the tank body;
the bottom of the tank body having one or more first slits formed over the full width of the bottom in a parallel relationship in the width direction; and
a metallic reinforcement member having an outer periphery which conforms to the contour of the tank body, the reinforcement member having at its top a slit fitting portion which mates with the first slit, the reinforcement member having at its both sides a pair of second slits into which the two sidewalls are inserted;
wherein the top of the reinforcement member is fitted in the first slit of the tank body, with the pair of second slits of the reinforcement member clamping both sides of the tank body, to thereby provide a liquid-tight connection therebetween.
According to a second aspect of the present invention there is provided a heat exchanger tank structure comprising:
a tank body formed from a bent metal plate in the shape of an elongated groove, the tank body having a bottom and two parallel sidewalls;
a tube plate having an open side which confronts the bottom of the tank body, the open side adapted to securely be fitted to the tank body;
the bottom of the tank body having, at its intermediate portion in the longitudinal direction, one or more intermediate first slits formed over the full width of the bottom in a parallel relationship in the width direction; and
a metallic reinforcement member in the shape of a gate in plan having at its top a slit fitting portion adapted to mate with the intermediate first slit, the reinforcement member including two legs having a pair of intermediate second slits into which the two sidewalls of the tank body are inserted;
wherein the top of the reinforcement member is fitted in the intermediate first slit of the tank body, with the pair of intermediate second slits of the reinforcement member clamping both sides of the tank body, to thereby provide a liquid-tight connection therebetween.
According to a third aspect of the present invention there is provided a heat exchanger tank structure comprising:
a tank body formed from a bent metal plate in the shape of an elongated groove, the tank body having a bottom and two parallel sidewalls;
a tube plate in the shape of a shallow groove having an open side which confronts the bottom of the tank body, the open side adapted to securely be fitted to the tank body;
the bottom of the tank body having a pair of end first slits formed over the full width of the bottom in a parallel relationship in the width direction; and
a pair of reinforcement side lids having an outer periphery which conforms to the grooved-shaped section of the tank body, the pair of reinforcement side lids each having at its bottom edge a slit fitting portion which mates with corresponding one of the pair of end first slits, the pair of reinforcement side lids each having a pair of end second slits which receive the sidewalls of the tank body, the pair of reinforcement side lids each having a protrusion formed on an edge confronting the tube plate;
the tube plate having a pair of locking holes formed in the tube plate at its opposite ends, the locking hole adapted to mate with the protrusion;
wherein the top of each of the pair of reinforcement side lids is fitted in corresponding one of the pair of end first slits such that the pair of end second slits clamp the two sidewalls of the tank body and that the protrusions are fitted in the locking holes of the tube plate, to thereby provide a liquid-tight connection therebetween.
The first slit may extend through the full width of the bottom of the tank body and, contiguous therewith, through a part of the two sidewalls in the region of the bottom, and the second slit may be inserted through the edges of the first slit associated with the sidewalls into the tube plate.